manage multi-remotes

[AlexandreMary]

Description

To cope with the issue described in Issue #39, has been implemented the following:

For each git project of the bundle:

• when the remote name is not provided in the bundle, if the repository exists, the registered remotes are explored:
• if a registered remote has the same url as the requested url, its remote name is used
• if no registered remote has the same url, it is added, with a remote name generated uniquely from the url
• the unicity is ensured by hashing the url; it is not very readable, open to any better idea.

Contributor Declaration

By opening this pull request, I affirm the following:

• All authors agree to the Contributor License Agreement.
• The code follows the project's coding standards.
• I have performed self-review and added comments where needed.
• I have added or updated tests to verify that my changes are effective and functional.
• I have run all existing tests and confirmed they pass.